Dustproof guard



May 3, 1927.

A. W. WADSWORTH DUSTPROOF' GUARD Filed March 12.. 1925 INVE/VTGP Arthur W Wadsw@vt h.

.4 TTQENE Y Patented May 3,1927.

UNITED STATES PATENT OFFICE.

ARTHUR W. WADSWORTH, OF FORT THOMAS, KENTUCKY, ASSIGNOR TO THE WADS- WORTH WATCH CASE COMPANY, OF DAYTON, KENTUCKY, A CORPORATION OF KENTUCKY.

DUSTPBOOF GUARD.

Application filed. March 12, 1925. Serial No. 14,947.

My invention relates to means tor preventing dust and dirt from gettinglnto the opening around the stem of a two-plece watchcase. g

The objects of my invention are to provide a simple, eflicient, serviceable and economical guard and means for holding 1t in a twopiece watchcase for the purpose of preventing dirt, dust, and the like fromgetting into thewatchcase through the usual opening around the winding stem in the watchcaseg;

My invention consists in providing a hollow uard havin members thereon engaging the inside an outside-of the walls of the watchcase, whereb said guard is held in position by said we is when the watchcase 1S closed or the parts thereof are put together.

My invention also consists in the part-9 and in the construction, combinat1on, loca tion and arrangement of parts, as herein set forth and claimed.

1n the drawing:'

Fig. 1 shows my dust-proof tube and crown in central vertical section and the relation of the tube with the two-piece watchcase, the latter shown partly in section and partly by dotted lines;

Fig. 2 is a vertical section of the crown before receiving the tube, the dotted lines indicating the part burnished over after the tube has been received;

Fig. 3 is a vertical section of the dustproot' tube; 0

Fig, 4 is an enlarged vertical section 81mllar to Fig. 1 but showing the crown and stem in the pulled out or setting position; a Fig. 5 is a perspective view of the crown dust-proof tube and stem, the first two parts being shown in vertical section; and

Fi 6 is an isometric view of the dust- .proo tube.

Heretofore in the manufacture of twopiece watchcases it has been the practice to provide a hole through the two ad acent parts of the watchcase to receive thew1ndmg and setting stem. This hole was somewhat larger in cross section than the start: in order to permit its insertion, thus leaving considerable spade around the stem throng which dirt, dust and-the like was readilyadmitted, thereb subjecting the movements to damage there rem.

In the embodiment of my: invention, as illustrated and which shows a preferred conturning it in winding.

vided with spaced apart outwardly extending annular flanges {1 and 4 at one end to form annular groove 5 which receives the adjacentabutting edges of the back 6 and front or bezel 7 of the watchcase between said annular flanges adjacent to said hole, thereb forming, a close dust-proof connection 0' said guard with said back and bezel and at the same time permitting lateral movement or play of said guard relative to the'back and bezel for the purpose of. permitting the stem to adapt itself to any variation in the location of the parts, of the movement to which said stem 1s connected.

The other end of said guard is provided with an inturned flange 8.

The crown 9 comprises a knurled knob and serves as convenient means to ull the stem outwardly for settin the watc or for hecrown is provided with a deep annular channel 11 to re ceive theinwardly flanged end of the guard and this channel is extended laterally adjacent the surface to provide an annular recess 12 to partly receive flange 4 of the guard toetfect a more compact and close fit of the parts. The crown is also provided with central stud or boss 13 havin an internally threaded socket 14 into whic the windin and setting stem 10 is screwed and hel There is also slight play between the inturned flange 8 and boss 13 to permit the stem to be readily pulled outwardly for setting the watch, as shown in Fig. 4.

In assembling the parts boss 13 is inserted through the inturned flanged end of the guard and the free end of the boss is then burnished to form an annular rim 15 to prevent the unintentional detachment of the crown even though the inner end of the stem should become disconnected from the works or watch movement. The stem 10 is then screwed into position into socket 14. The back 6 and bezel 7 are then snapped together and into annular groove 5 between the flanges 4 and 4 ad'acent stem-hole 2. The parts are thus hel in position relative to each other and the crown is adapted to be pulled outwardly relative to the guard which I at all times maintains its dust-proof relation with the crown and with the back and bezel, thus etficiently serving to exclude dust, dirt and the like under all conditions and position of the parts relative to each other.

It is thus seen that I have produced a very simple, yet elficient and economical dustproof construction for a two-piece watchcase.

While I have shown a particular construction, it is understood that my invention is capable of modification without departure from its scope or spirit, as defined in the claims.

I claim:

1. In dust-proof guards for a two-piece watchcase havin a stem-hole in one ed e, a crown having a oss with an annular c annel therearound, a tubular guard having an inturned flange at one and adapted to be slidably secured on said boss, a stem secured to said boss, said guard having on its other end spaced a art flanges forming an annalar groove a apted to receive the adjacent edges of the back and bezel, respectively, surrounding said stem-hole whereby a dustproof connection is formed between said guard and crown and between said guard and said back and bezel.

2. In a dust-proof guard for a two-piece watchcase having a stem-hole, a crown having a boss with an annular channel therearound and an annular recess adjacent said annular channel, a tubular guard having an inwardly flanged end adapted to closely fit and be slidably mounted on said boss, means on said boss to hold said crown in 0 rative relation with said guard, said guard having spaced apart flan es forming a groove adapted to receive t e adjacent edges of the back and bezel surrounding said hole whereby a close fit is obtained between said case and guard and whereby one of said flanges is adapted to fit in said annular recess to provide compactness.

3. In a dust-proof guard for a two-piece watchcase having a stem-hole, a tubular ard detachably mounted in said hole and orming a close connection with said case, and a crown slidably mounted on said guard and forming a close connection therewith.

4. A guard for a watchcase comprising a tube or sleeve having outwardly extending spaced apart flanges forming a roove at one end and having an inturned an e at the other end, for the purposes specified.

5. In a dust-proof guard, a crown havin a boss, a tubular flanged guard in which sai boss is slidably mounted, and means for preventiig detachment of said crown from said uar c 6. In a dust-proof uard for a two-piece watchcase, a crown aving an internally threaded boss with an annular channel therearound, a tubular guard having an inturned flange closely fitting said boss which is slidable therein, and a rim formed on said boss whereby it is held from disengagement from said guard, a stem screwed in said boss, and means for mounting said guard upon a watchcase.

7. A guard for a two-piece watchcase comprising a tubular member having spaced apart flanges thereon forming a groove adapted to receive the adjacent edges of the back and bezel of said watchcase whereb it is held in position and forms an eflicient ust guard. l

ARTHUR W. WADSWORTH. 

